Electrochemical CellsTechniques involved in measuring the voltage of an electrochemical cell and some common errors in constructing electrochemical cells are demonstrated.

Electrolytic / Galvanic Cells / Potentials |

Laboratory Equipment / Apparatus

Oscillating Reaction: Briggs-RauscherWhen a solution of malonic acid, starch, and manganese(II) ion is added to a solution of hydrogen peroxide, iodate ion, and sulfuric acid, gas bubbles form and the color of the resulting mixture oscillates periodically from colorless to amber to blue.

Orange Juice ClockIn this demonstration a galvanic cell is made from the combination of a magnesium strip, a copper strip, and juice in a beaker. The current from this cell is used to drive a clock normally powered by a DC battery.

Electrolytic / Galvanic Cells / Potentials |

Oxidation / Reduction

Electrical PropertiesUse of the conductivity meter and techniques for measuring voltage of electrochemical cells are demonstrated.

Conductivity |

Laboratory Equipment / Apparatus |

Electrolytic / Galvanic Cells / Potentials

Electrochemical Series: Metal TreesA piece of metal (Cu, Zn, Ag, Cd, or Pb) is placed in an aqueous solution of a metal ion (Cu2+, Zn2+, Ag+, Cd2+, or Pb2+). In some cases the growth of metal crystals indicates that a chemical reaction has occurred.

Aqueous Solution Chemistry |

Oxidation / Reduction |

Electrolytic / Galvanic Cells / Potentials |

Electrochemistry

Pulsating Electrochemical Reaction: Mercury Beating HeartA drop of mercury in a watch glass is covered with a solution of potassium chromate in concentrated sulfuric acid. An iron nail is positioned so that it nearly touches the mercury. Eventually, the mercury drop starts to beat rhythmically, like a beating heart.